Download VOKERA Mynute Technical data

Mynute
Standard efficiency system boiler
12e - 16e - 20e
Installation
& Servicing
Instructions
THESE INSTRUCTIONS
TO BE RETAINED
BY USER
Vokèra is a licensed member of the Benchmark scheme
which aims to improve the standards of installation and
commissioning of domestic hot water systems in the UK.
Contents
Design principles and operating sequence
1.1
Principle components
1.2
Mode of operation
1.3
Safety devices
Page
2
2
2
Technical data
2.1
Performance
2.2
Gas pressure
2.3
Expansion vessel
2.4
Dimensions
2.5
Clearances
2.6
Connections
2.7
Electrical
2.8
Flue details
2.9
Efficiency
2.10
Pump duty
Page
3
3
3
3
3
3
3
3
3
4
General requirements (UK)
3.1
Related documents
3.2
Location of appliance
3.3
Gas supply
3.4
Flue system
3.5
Air supply
3.6
Water circulation
3.6.1 Pipework
3.6.2 Automatic by-pass
3.6.3 Drain cocks
3.6.4 Air release points
3.6.5 Expansion vessel
3.6.6 Filling point
3.6.7 Low pressure sealed system
3.6.8 Frequent filling
3.7
Electrical supply
3.8
Showers
3.9
Mounting on a combustible surface
3.10
Timber framed building
3.11
Inhibitors
Page
5
5
5
5
5
5
6
6
6
6
6
6
6
6
6
6
6
6
7
General requirements (EIRE)
3.A1
Related documents
3.A2
Location of appliance
3.A3
Gas supply
3.A4
Flue system
3.A5
Air supply
3.A6
Water circulation
3.A6.1 Pipework
3.A6.2 Automatic by-pass
3.A6.3 Drain cocks
3.A6.4 Air release points
3.A6.5 Expansion vessel
3.A6.6 Filling point
3.A6.7 Low pressure sealed system
3.A6.8 Frequent filling
3.A7
Electrical supply
3.A8
Showers
3.A9
Mounting on a combustible surface
3.A10 Timber framed building
3.A11 Inhibitors
3.A12 Declaration of conformity
Page
7
7
7
7
7
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
Installation
4.1
Delivery
4.2
Contents
4.3
Unpacking
4.4
Preparation for mounting the appliance
4.4.1 Important
4.4.2 Maximum flue lenghts
4.5
Fitting the flue
4.5.1 Concentric horizontal flue
4.5.2 Concentric vertical flue
4.5.3 Twin flue system
4.5.3.1 Installation of twin adaptor kit
4.5.3.2 Installation of condensate drain kit
4.5.3.3 Horizontal termination
4.5.3.4 Vertical termination
4.6
Connecting the gas and water
4.6.1 Gas
4.6.2 Flow and return
4.6.3 Safety valve
4.7
Electrical connections
4.7.1 Casing removal
4.7.2 Appliance terminal block
4.7.3 Connecting the mains (230V) input
Page
9
9
9
9
9
9
9
9
11
11
12
12
12
12
14
14
14
14
14
14
14
15
Commissioning
5.1
Gas supply installation
5.2
The heating system
5.3
Initial filling of the system
5.4
Initial flushing
5.5
Pre-operation checks
5.6
Initial lighting
5.7
Checking burner pressures
5.8
Final flushing of the heating system
5.9
Setting the boiler operating temperature
5.10
Setting the system design pressure
5.11
Regulating the central heating system
5.12
Final checks
5.13
Instructing the user
Page
16
16
16
16
16
16
16
16
16
16
17
17
17
Servicing instructions
6.1
General
6.2
Routine annual servicing
6.3
Replacement of components
6.4
Component removal procedure
6.5
Pump head
6.6
Safety valve
6.7
Automatic air release valve
6.8
Water pressure switch
6.9
Pressure gauge
6.10
NTC thermistors
6.11
High limit thermostat
6.12
PCB
6.13
Gas valve
6.14
Integral time switch
6.15
Burner, injectors and spark electrode
6.16
Flue fan
6.17
Heat exchanger
6.18
Air pressure switch
6.19
Expansion vessel
6.19.1 Expansion vessel (removal)
Page
18
18
18
18
18
18
18
19
19
19
19
19
19
19
20
20
20
21
21
21
Checks, adjustments and fault finding
7.1
Checking appliance operation
7.2
Appliance mode of operation
7.3
Checking burner pressure
7.4
Combustion analysis test
7.5
Checking the expansion vessel
7.6
External faults
7.6.1 Installation faults
7.7
Electrical checks
7.7.1 Earth continuity test
7.7.2 Short circuit check
7.7.3 Polarity check
7.7.4 Reversed polarity or supply fault
7.7.5 Resistance to earth check
page
22
22
22
22
22
23
23
23
23
23
23
23
23
Wiring diagrams
8.1
‘Y’ plan using an external programmer
8.2
‘S’ plan using an external programmer
8.3
‘Y’ plan with Vokera twin channel programmer
8.4
‘S’ plan with Vokera twin channel programmer
8.5
Installation of Vokera time clock
8.6
Installation of Vokera twin channel programmer
Functional diagram
Page
26
26
27
27
28
28
29-30
Exploded diagrams
Table 1
Table 2
Table 3
Table 4
Table 5
Page
31
32
33
34
35
L.P.G. instructions
10.1
Technical data
10.2
Related documents
10.3
Gas supply
10.4
Gas supply installation
10.5
Burner pressures
Page
36
36
36
36
36
INTRODUCTION
The Vokera 12, 16, and 20e Mynutes are central heating
boilers, which – by design – incorporate electronic
ignition, circulating pump, expansion vessel, safety valve,
pressure gauge, and automatic by-pass.
They are produced as room sealed, category II2H3+
appliances, suitable for wall mounting applications only.
They are provided with a fan powered flue outlet with an
annular co-axial combustion air intake that can be rotated
– horizontally – through 360 degrees for various horizontal
or vertical applications.
The Mynute range can also be used with the Vokera twin
flue system.
These appliances are designed for use with sealed
systems only; consequently they are not intended for use
on open vented systems.
The provision of stored hot water is possible by the
addition of an indirect cylinder.
A range rating facility is incorporated in the appliance.
1
24
2
23
3
Fig.1 General Layout
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
22
5
6
21
7
20
8
19
18
17
9
16
15
13
12
Flue outlet
Air intake
Pressure differential switch
Silicone tubes (pressure diff. switch)
Heat exchanger
NTC thermistor
High limit thermostat
Spark/sensing electrode
Gas valve
Clock aperture
Pressure gauge
Thermostat
Mode switch
Warning led
Water pressure switch
Safety valve
Pump
Automatic air vent
Burner
Expansion vessel
Combustion chamber
Fan
Air chamber
Flue gas analysis test point
11
10
14
Fig. 1
Mynute
1
SECTION 1: DESIGN PRINCIPLES AND OPERATING SEQUENCE
1.1
PRINCIPLE COMPONENTS
A fully integrated electronic control board
featuring mode switch, temperature control,
electronic ignition and flame supervision, anticycle control, pump over-run, and appliance
fault indicator.
● Low water content copper heat exchanger.
● Integral pump
● Fan
● Expansion vessel
● Differential air pressure switch
● Water pressure switch
● Two-stage gas valve
● Pressure gauge
● Safety valve
●
1.2
MODE OF OPERATION
When there is a request for heat and/or hot water
via the programmer/time clock and/or any
external control, the pump and fan are started,
the fan proves the differential air pressure switch
which in-turn allows an ignition sequence to
begin.
Ignition is sensed by the electronic circuitry to
ensure flame stability at the burner. Once
successful ignition has been achieved, the
electronic circuitry allows full gas rate through
the appliance.
When the appliance reaches the desired
temperature the burner will shut down and the
boiler will perform a three-minute anti-cycle (timer
delay).
When the request for heat and/or hot water has
been satisfied the appliance pump will continue
to circulate for a period of 30 seconds to dissipate
any residual heat within the appliance.
1.3
2
SAFETY DEVICES
When the appliance is in use, safe operation is
ensured by:
● a water pressure switch that monitors system
water pressure and will de-activate the pump,
fan, and burner should the system water
pressure drop below the rated tolerance.
● a high limit thermostat that over-rides the
temperature control circuit to prevent or
interrupt the operation of the burner.
● a differential air pressure switch that checks
the operation of the fan and flue thereby
allowing safe operation of the burner.
● a safety valve which releases excess pressure
from the primary circuit.
5
6
7
20
gas
18
17
15
16
return
flow
Fig. 2
Mynute
SECTION 2: TECHNICAL DATA
2.1 PERFORMANCE
Heat input
Heat output (max)
Heat output (min)
Minimum working pressure
Maximum working pressure
Minimum flow rate
12e
13.0 kW
12.0 kW
7.4 kW
0.5 bar
3.0 bar
350 l/hour
16e
17.7 kW
16.0 kW
12.0 kW
0.5 bar
3.0 bar
350 l/hour
20e
21.8 kW
19.8 kW
14.0 kW
0.5 bar
3.0 bar
350 l/hour
12e
20 mbar
8.8 mbar
1.38 m3/h
7x1.30 mm
16e
20 mbar
8.4 mbar
1.87 m3/h
9x1.35 mm
20e
20 mbar
12.3 mbar
2.31 m3/h
9x1.35 mm
12e
6.0 litres
63 litres
1.0 bar
16e
6.0 litres
63 litres
1.0 bar
20e
6.0 litres
63 litres
1.0 bar
2.2 GAS PRESSURE
Inlet pressure (G20)
Maximum burner pressure
Gas rate
Injector size
2.3 EXPANSION VESSEL
Capacity
Maximum system volume
Pre-charge pressure
2.4 DIMENSIONS (all models)
Height
740 mm
Width
Depth
Weight
366 mm
315 mm
30 kg
2.5 CLEARANCES (all models)
Top
150 mm from casing or 25mm above flue elbow (whichever is applicable)
Bottom
Sides
Front
150 mm
12 mm
600 mm
2.6 CONNECTIONS (all models)
Flow & return
22 mm compression
Gas
Safety valve
15 mm compression
1/2in. BSP
2.7 ELECTRICAL (all models)
Voltage
Power consumption
Internal fuse
External fuse
230V/50hz
125 W
2 AL
3A
2.8 FLUE DETAILS
Maximum horizontal flue length (concentric)
Maximum vertical flue length (concentric)
Maximum twin flue length (horizontal or vertical)
12e
4.5 metres
5.5 metres
14m/14m + terminal
16e & 20e
3.4 metres
4.4 metres
14m/14m + terminal
16e
79.62%
20e
78.05 %
2.9 EFFICIENCY
SEDBUK rating
Appliance type
Category
Mynute
12e
79.15%
C12 - C22 - C32
IP20
3
SECTION 2: TECHNICAL DATA
2.10
PUMP DUTY
Fig. 3 shows the flow-rate available – after allowing for pressure loss through the appliance – against system
pressure loss. When using this graph apply only the pressure loss of the system. The graph is based on a
20ºC temperature differential.
600
Water pressure (mbar)
500
400
300
200
100
0
1
2
Fig. 3
3
4
5
6
7
8
9
10
11
12
13
Litres Per Hour (x100)
Fig. 4
Key
A
B
C
D
E
F
G
H
I
J
K
L
M
N
P
Q
4
Location
Below an opening (window, air-brik, etc.)
Above an opening (window, air-brik, etc.)
To the side of an opening (window, air-brik, etc.)
Below gutter, drain-pipe, etc.
Below eaves
Below balcony, car-port roof, etc.
To the side of a soil/drain-pipe, etc.
From internal/external corner or boundary
Above ground, roof, or balcony level
From a surface or boundary facing the terminal
From a terminal facing a terminal
From an opening in the car-port into the building
Vertically from a terminal on the same wall
Horizontally from a terminal on the same wall
From a structure to the side of the vertical terminal
From the top of the vertical terminal to the roof flashing
Minimum distance
300 mm
300 mm
300 mm
75 mm
200 mm
200 mm
150 mm
300 mm
300 mm
600 mm
1200 mm
1200 mm
1500 mm
300 mm
300 mm
As determined by the fixed collar
of the vertical terminal
Mynute
SECTION 3: GENERAL REQUIREMENTS (UK)
This appliance must be installed by a competent
person in accordance with the Gas Safety
(Installation & Use) Regulations.
3.1
3.2
RELATED DOCUMENTS
The installation of this boiler must be in accordance
with the relevant requirements of the Gas Safety
(Installation & Use) Regulations, the local building
regulations, the current I.E.E. wiring regulations,
the bylaws of the local water undertaking, the
Building Standards (Scotland) Regulation, and
Building Standards (Northern Ireland)
Regulations.
It should be in accordance also with any relevant
requirements of the local authority and the
relevant recommendations of the following British
Standard Codes of Practice.
3.3
GAS SUPPLY
The gas meter – as supplied by the gas supplier
– must be checked to ensure that it is of adequate
size to deal with the maximum rated input of all
the appliances that it serves. Installation pipes
must be fitted in accordance with BS 6891.
Pipe work from the meter to the appliance must
be of adequate size. Pipes of a smaller size than
the appliance gas inlet connection must not be
used. The installation must be tested for
soundness in accordance with BS6891.
If the gas supply serves more than one appliance,
it must be ensured that an adequate supply is
maintained to each appliance when they are in
use at the same time.
3.4
FLUE SYSTEM
The terminal should be located where the dispersal
of combustion products is not impeded and with
due regard for the damage and discoloration that
may occur to building products located nearby.
The terminal must not be located in a place where
it is likely to cause a nuisance (see fig. 4).
In cold and/or humid weather, water vapour may
condense on leaving the terminal; the effect of
such pluming must be considered.
If installed less than 2m above a pavement or
platform to which people have access (including
balconies or flat roofs) the terminal must be
protected by a guard of durable material. The
LOCATION OF APPLIANCE
The appliance may be installed in any room or
internal space, although particular attention is
drawn to the requirements of the current I.E.E.
wiring regulations, and in Scotland, the electrical
provisions of the Building Regulations, with
respect to the installation of the appliance in a
room or internal space containing a bath or shower.
When an appliance is installed in a room or
internal space containing a bath or shower, the
appliance or any control pertaining to it must not
be within reach of a person using the bath or
shower.
BS 5440
BS 5440
BS 5449
BS 5546
BS 6798
BS 6891
BS 7074
PART 1
PART 2
PART 1
PART 1
FLUES
FLUES AND VENTILATION
FORCED CIRCULATION HOT WATER SYSTEMS
INSTALLATION OF GAS HOT WATER SUPPLIES FOR DOMESTIC PURPOSES
(2ND FAMILY GASES)
BOILERS OF RATED INPUT NOT EXCEEDING 60kW
LOW PRESSURE INSTALLATION PIPES
APPLICATION, SELECTION AND INSTALLATION OF EXPANSION VESSELS AND
ANCILLARY EQUIPMENT FOR SEALED WATER SYSTEMS
The location chosen for the appliance must permit
the provision of a safe and satisfactory flue and
termination. The location must also permit an
adequate air supply for combustion purposes
and an adequate space for servicing and air
circulation around the appliance. Where the
installation of the appliance will be in an unusual
location special procedures may be necessary,
BS 6798 gives detailed guidance on this aspect.
guard must be fitted centrally over the terminal.
Refer to BS 5440 Part 1, when the terminal is 0.5
metres (or less) below plastic guttering or 1 metre
(or less) below painted eaves.
3.5
AIR SUPPLY
The following notes are intended for general
guidance only.
This appliance is a room-sealed, fan-flued boiler,
consequently it does not require a permanent air
vent for combustion air supply.
When installed in a cupboard or compartment,
ventilation for cooling purposes is also not
required.
3.6
WATER CIRCULATION
Detailed recommendations are given in BS 5449
Part 1 and BS 6798. The following notes are for
general guidance only.
A compartment used to enclose the appliance
must be designed and constructed specifically
for this purpose. An existing compartment/
cupboard may be utilised provided that it is
modified to suit.
Details of essential features of compartment/
cupboard design including airing cupboard
installations are given in BS 6798. This appliance
is not suitable for external installation.
Mynute
5
SECTION 3: GENERAL REQUIREMENTS (UK)
3.6.1
PIPEWORK
It is recommended that copper tubing to BS 2871
Part 1 is used in conjunction with soldered capillary
joints. Where possible pipes should have a
gradient to ensure air is carried naturally to air
release points and that water flows naturally to
drain cocks. Except where providing useful heat,
pipes should be insulated to avoid heat loss and
in particular to avoid the possibility of freezing.
Particular attention should be paid to pipes passing
through ventilated areas such as under floors, loft
space, and void areas.
3.6.2
AUTOMATIC BY-PASS
The appliance has a built-in automatic by-pass,
consequently there is no requirement for an external
by-pass, however the design of the system should
be such that it prevents boiler § ‘cycling’.
3.6.3
3.6.4
3.6.5
3.6.6
Fig. 5
6
3.6.7
make-up vessel or tank
auto air vent
DRAIN COCKS
These must be located in accessible positions to
facilitate draining of the appliance and all water
pipes connected to the appliance. The drain
cocks must be manufactured in accordance with
BS 2879.
AIR RELEASE POINTS
These must be positioned at the highest points in
the system where air is likely to be trapped. They
should be used to expel trapped air and allow
complete filling of the system.
EXPANSION VESSEL
The appliance has an integral expansion vessel
to accommodate the increased volume of water
when the system is heated. It can accept up to
6.0 litres of expansion from within the system,
generally this is sufficient, however if the system
has an unusually high water content, it may be
necessary to provide additional expansion
capacity (see 6.19).
LOW PRESSURE SEALED SYSTEM
An alternative method of filling the system would
be from an independent make-up vessel or tank
mounted in a position at least 1 metre above the
highest point in the system and at least 5 metres
above the boiler (see fig. 5A).
The cold feed from the make-up vessel or tank
must be fitted with an approved non-return valve
and stopcock for isolation purposes. The feed
pipe should be connected to the return pipe as
close to the boiler as possible.
1 metre minimum
the highest point
the system, and
metres minimum
the appliance
stop-cock
to
of
5
to
non-return valve
heating return (at boiler)
Fig. 5a
3.6.8
FREQUENT FILLING
Frequent filling or venting of the system may be
indicative of a leak. Care should be taken during
the installation of the appliance to ensure all
aspects of the system are capable of withstanding
pressures up to at least 3 bar.
3.7
ELECTRICAL SUPPLY
The appliance is supplied for operation on 230V
@ 50Hz electrical supply; it must be protected
with a 3-amp fuse. The method of connection to
the mains electricity supply must allow for
complete isolation from the supply. The preferred
method is by using a double-pole switch with a
contact separation of at least 3mm. The switch
must only supply the appliance and its
corresponding controls, i.e. time clock, room
thermostat, etc. Alternatively an un-switched
shuttered socket with a fused 3-pin plug both
complying with BS 1363 is acceptable.
3.8
SHOWERS
If the appliance is intended for use with a shower,
the shower must be thermostatically controlled
and be suitable for use with a combination boiler.
3.9
MOUNTING ON A COMBUSTIBLE SURFACE
If the appliance is to be fitted on a wall of
combustible material, a sheet of fireproof material
must protect the wall.
3.10
TIMBER FRAMED BUILDINGS
If the appliance is to be fitted in a timber framed
building, it should be fitted in accordance with the
Institute of Gas Engineers publication (IGE/UP/
7) ‘Guide for Gas Installations in Timber Frame
Buildings’.
FILLING POINT
A method for initial filling of the system and replacing
water lost during servicing etc. must be provided.
This method of filling must comply with the current
Water Supply (Water Fittings) Regulations 1999
and Water Bylaws 2000 (Scotland). Fig. 5 shows a
widely accepted method.
Mynute
SECTION 3: GENERAL REQUIREMENTS (UK)
3.11
INHIBITORS
Vokera recommend that a neutral inhibitor is
used to protect the heating system from the
effects of corrosion and/or electrolytic action.
The inhibitor must be administered in strict
accordance with the manufacturers* instructions.
*Fernox and Sentinel manufacture products that
have proved suitable for use with Vokera
appliances. Vokera Ltd. cannot comment on the
suitability of any other such product with our
appliances.
return
flow
gas
Fig. 6
SECTION 3A: GENERAL REQUIREMENTS (EIRE)
This appliance must be installed by a competent
person in accordance with and defined by, the
Standard Specification (Domestic Gas
Installations) Declaration (I.S. 813).
3A.1
RELATED DOCUMENTS
The installation of this boiler must be in accordance
with the relevant requirements of the local building
regulations, the current ETCI National Rules for
Electrical Installations, and the bylaws of the
local water undertaking.
It should be in accordance also with any relevant
requirements of the local and/or district authority.
3A.2
LOCATION OF APPLIANCE
The appliance may be installed in any room or
internal space, although particular attention is
drawn to the requirements of the current ETCI
National Rules for Electrical Installations, and
I.S. 813, Annex K.
When an appliance is installed in a room or internal
space containing a bath or shower, the appliance
or any control pertaining to it must not be within
reach of a person using the bath or shower.
The location chosen for the appliance must permit
the provision of a safe and satisfactory flue and
termination. The location must also permit an
adequate air supply for combustion purposes
and an adequate space for servicing and air
circulation around the appliance. Where the
installation of the appliance will be in an unusual
location special procedures may be necessary,
refer to I.S. 813 for detailed guidance on this
aspect. A compartment used to enclose the
appliance must be designed and constructed
specifically for this purpose. An existing
compartment/cupboard may be utilised provided
that it is modified to suit. This appliance is not
suitable for external installation.
Mynute
3A.3
GAS SUPPLY
The gas meter – as supplied by the gas supplier
– must be checked to ensure that it is of adequate
size to deal with the maximum rated input of all
the appliances that it serves. Installation pipes
must be fitted in accordance with I.S. 813.
Pipe work from the meter to the appliance must
be of adequate size. Pipes of a smaller size than
the appliance gas inlet connection must not be
used. The installation must be tested for
soundness in accordance with I.S. 813.
If the gas supply serves more than one appliance,
it must be ensured that an adequate supply is
maintained to each appliance when they are in
use at the same time.
3A.4
FLUE SYSTEM
The terminal should be located where the dispersal
of combustion products is not impeded and with
due regard for the damage and discoloration that
may occur to building products located nearby.
The terminal must not be located in a place where
it is likely to cause a nuisance (see I.S. 813).
In cold and/or humid weather, water vapour may
condense on leaving the terminal; the effect of
such pluming must be considered.
If installed less than 2 m above a pavement or
platform to which people have access (including
balconies or flat roofs) the terminal must be
protected by a guard of durable material. The
guard must be fitted centrally over the terminal.
Refer to I.S. 813, when the terminal is 0.5 metres
(or less) below plastic guttering or 1 metre (or
less) below painted eaves.
3A.5
AIR SUPPLY
The following notes are intended for general
guidance only. This appliance is a room-sealed,
fan-flued boiler, consequently it does not require
7
SECTION 3A: GENERAL REQUIREMENTS (EIRE)
a permanent air vent for combustion air supply.
When installed in a cupboard or compartment,
ventilation for cooling purposes is also not
required.
3A.6
WATER CIRCULATION
Specific recommendations are given in I.S. 813.
The following notes are for general guidance
only.
3A.6.1 PIPEWORK
It is recommended that copper tubing be used in
conjunction with soldered capillary joints.
Where possible pipes should have a gradient to
ensure air is carried naturally to air release points
and that water flows naturally to drain cocks.
Except where providing useful heat, pipes should
be insulated to avoid heat loss and in particular to
avoid the possibility of freezing. Particular attention
should be paid to pipes passing through ventilated
areas such as under floors, loft space, and void
areas.
The cold feed from the make-up vessel or tank
must be fitted with an approved non-return valve
and stopcock for isolation purposes. The feed
pipe should be connected to the return pipe as
close to the boiler as possible.
3A.6.8 FREQUENT FILLING
Frequent filling or venting of the system may be
indicative of a leak. Care should be taken during
the installation of the appliance to ensure all
aspects of the system are capable of withstanding
pressures up to at least 3 bar.
3A.7
ELECTRICAL SUPPLY
The appliance is supplied for operation on 230V
@ 50Hz electrical supply; it must be protected
with a 3-amp fuse. The method of connection to
the mains electricity supply must allow for
complete isolation from the supply. The preferred
method is by using a double-pole switch with a
contact separation of at least 3 mm. The switch
must only supply the appliance and its
corresponding controls, i.e. time clock, room
thermostat, etc.
3A.8
SHOWERS
If the appliance is intended for use with a shower,
the shower must be thermostatically controlled
and be suitable for use with a combination boiler.
3A.6.3 DRAIN COCKS
These must be located in accessible positions to
facilitate draining of the appliance and all water
pipes connected to the appliance.
3A.9
MOUNTING ON A COMBUSTIBLE SURFACE
If the appliance is to be fitted on a wall of
combustible material, a sheet of fireproof material
must protect the wall.
3A.6.4 AIR RELEASE POINTS
These must be positioned at the highest points in
the system where air is likely to be trapped. They
should be used to expel trapped air and allow
complete filling of the system.
3A.10 TIMBER FRAMED BUILDINGS
If the appliance is to be fitted in a timber framed
building, it should be fitted in accordance with I.S.
813 and local Building Regulations.
The Institute of Gas Engineers publication (IGE/
UP/7) ‘Guide for Gas Installations in Timber Frame
Buildings’ gives specific advice on this type of
installation.
3A.6.2 AUTOMATIC BY-PASS
The appliance has a built-in automatic by-pass,
consequently there is no requirement for an
external by-pass, however the design of the
system should be such that it prevents boiler
‘cycling’.
3A.6.5 EXPANSION VESSEL
The appliance has an integral expansion vessel
to accommodate the increased volume of water
when the system is heated. It can accept up to 6
litres of expansion from within the system,
generally this is sufficient, however if the system
has an unusually high water content, it may be
necessary to provide additional expansion
capacity (see section 6.19).
3A.6.6 FILLING POINT
A method for initial filling of the system and
replacing water lost during servicing etc. has
been provided. You should ensure this method of
filling complies with the local water authority
regulations.
3A.6.7 LOW PRESSURE SEALED SYSTEM
An alternative method of filling the system would
be from an independent make-up vessel or tank
mounted in a position at least 1 metre above the
highest point in the system and at least 5 metres
above the boiler (fig. 5a).
8
3A.11 INHIBITORS
Vokera recommend that a neutral inhibitor is
used to protect the heating system from the
effects of corrosion and/or electrolytic action.The
inhibitor must be administered in strict accordance
with the manufacturers* instructions.
*Fernox and Sentinel manufacture products that
have proved suitable for use with Vokera
appliances. Vokera Ltd. cannot comment on the
suitability of any other such product with our
appliances.
3A.12 DECLARATION OF CONFORMITY
A Declaration of Conformity (as defined in I.S.
813) must be provided on completion of the
installation.
A copy of the declaration must be given to the
responsible person and also to the gas supplier if
required.
Mynute
SECTION 4: INSTALLATION
4.1
DELIVERY
The appliance is delivered in a heavy-duty
cardboard carton. Lay the carton on the floor with
the writing the correct way up.
4.2
CONTENTS
Contained within the carton is:
• the boiler
• the wall mounting bracket
• template
• an accessories pack containing the appliance
service valves and washers
• the instruction pack containing the installation
& servicing instructions, user instructions,
Benchmark logbook, guarantee registration
card, a 3-amp fuse and flue restrictor ring.
4.3
4.4
UNPACKING
At the top of the carton pull both sides open – do
not use a knife – unfold the rest of the carton
from around the appliance, carefully remove all
protective packaging from the appliance, and lay
the accessories etc. to one side.
PREPARATION FOR MOUNTING THE
APPLIANCE
The appliance should be mounted on a smooth,
non-combustible, vertical surface, which must be
capable of supporting the full weight of the
appliance. Care should be exercised when
determining the position of the appliance with
respect to hidden obstructions such as pipes,
cables, etc.
When the position of the appliance has been
decided – using the template supplied – carefully
mark the position of the wall bracket (see fig. 7)
and flue-hole (if applicable).
1= centre of rear flue hole using ONLY 0225705 or 0225710 flue
2= centre of rear flue hole for ALL OTHER FLUES
Hole for
Room Sealed
appliance
(Rear Exit Flue)
4.4.1
IMPORTANT
There are two holes on the template. The lower
hole should be used with the telescopic flue
kit (part no. 0225705 & 0225710). The upper hole
is for use with all other horizontal flue kits.
4.4.2
MAXIMUM FLUE LENGTHS
Flue system
Mynute 12e
Mynute 16e/20e
Concentric Horizontal
4.25m
3.4m
Concentric Vertical
5.25m
4.4m
Twin flue
14m/14m + terminal 14m/14m + terminal
4.5
FITTING THE FLUE
The top flue outlet permits both horizontal and
vertical flue applications to be considered,
alternatively, the Vokera twin flue system can be
utilised if longer flue runs are required.
4.5.1
CONCENTRIC HORIZONTAL FLUE
(For concentric vertical flue, see 4.5.2)
(For twin flue applications, see 4.5.3)
The appliance flue outlet elbow can be rotated
through 360º on its vertical axis. In addition the
flue may be extended from the outlet elbow in the
horizontal plane (see 4.4.2), however if the flue is
to be extended or additional bends are to be
fitted, the standard horizontal flue kit (part no.
2359029) must be used. A reduction must also
be made to the maximum length (see table) when
additional bends are used.
Bend
Reduction in maximum flue
length for each bend
0.5 Metre
1.0 Metre
45º bend
90º bend
Horizontal flue terminals and accessories
Part No.
0225705
Description
Standard telescopic flue
Min-Max Length
380mm – 600mm
(Dimension ‘X’)
0225710
Extended telescopic flue
600mm – 920mm
2359029
2359069
Horizontal flue kit
For use with add. Bends
& extensions
750mm extension
833mm
(dimension ‘X’)
750mm
2359079
1500mm extension
1500mm
2359049
45º bend (pair)
N/A
2359059
90º bend
N/A
0225760
Wall bracket (5)
N/A
(Dimension ‘X’)
type 1 = centre of rear flue hole
using only 0225705 or
0225710 flue
type 2 = centre of rear flue hole
for all other flues
Using the template provided (see 4.4.1), mark and
drill a 125mm hole for the passage of the flue pipe.
The hole should have a 1º drop from the boiler to
outside, to eliminate the possibility of rainwater
entering the appliance via the flue.
Fig. 7
Mynute
The fixing holes for the wall-mounting bracket
should now be drilled and plugged, an appropriate
type and quantity of fixing should be used to
ensure that the bracket is mounted securely.
Once the bracket has been secured to the wall,
mount the appliance onto the bracket.
9
SECTION 4: INSTALLATION
Insert the flue restrictor ring (supplied with
instruction pack) into the appliance flue gas outlet
if the total flue length is less than 1.0 metre.
FITTING THE TELESCOPIC FLUE KIT (0225705
& 0225710)
Carefully measure the distance from the centre of
the appliance flue outlet to the face of the outside
wall (dimension ‘X’ see fig. 8). Add 50mm to
dimension ‘X’ to give the overall flue length
(dimension ‘Y’). Using the complete telescopic
flue assembly adjust the length to suit dimension
‘Y’. Once the telescopic flue terminal has been
adjusted to the correct length, secure the flue
assembly with the screw supplied.
If the horizontal flue kit (2359029) requires to be
cut to the correct size (dimension ‘Y’), you must
ensure that the inner (60mm) pipe stands proud of
the outer (100mm) pipe by 7.5mm (see fig. 8B).
Ensure any burrs are filed or removed and that
any seals are located properly before assembly.
Connect the inner (60mm) pipe of the terminal
assembly to the push-fit end of the 90º bend
(supplied) using a twisting action. Insert the
assembled flue into the previously drilled hole.
Using the clips & screws supplied, connect the
flue assembly to the boiler, ensuring that the
terminal protrudes past the finished outside wall
by the correct length (135mm).
Insert the flue restrictor ring (supplied in the
instruction pack) into the appliance flue gas outlet.
Slide the flue assembly into the previously drilled
flue hole and locate the flue bend over the appliance
flue outlet. Push the flue bend down over the
appliance flue outlet and ensure the correct seal
is made. Pull the flue assembly towards and over
the flue bend – using a twisting action – ensuring
the correct seal is made. Check that the terminal
protrudes past the finished outside wall by the
correct length (115mm).
You must ensure that the entire flue system is
properly supported and connected.
110
Dimension “Y”
7,5
115 mm
135 mm
Max. 833 mm
Fig. 8A
Dimension “X”
Seal the flue assembly to the wall using cement or
a suitable alternative that will provide satisfactory
weatherproofing. The exterior trim can now be
fitted.
“X” + 50 mm = “Y”
Fig. 8
NOTE
You must ensure that the entire flue system is
properly supported and connected.
Seal the flue assembly to the wall using cement or
a suitable alternative that will provide satisfactory
weatherproofing. The interior and exterior trim
can now be fitted.
FITTING THE STANDARD (2359029)
HORIZONTAL FLUE KIT (see 4.4.1)
Carefully measure the distance from the centre
of the appliance flue outlet to the face of the
outside wall (dimension ‘X’ see fig. 8A). Ensure
the inner (60mm) pipe is fully inserted into the
outer (100mm) pipe (when the inner pipe is fully
inserted, it stands proud of the outer pipe by
7.5mm). Add 32mm to dimension ‘X’ to give the
overall flue length (dimension ‘Y’). The standard
horizontal flue kit (part no. 2359029) is suitable
for a distance (dimension ‘Y’) of up to 865mm.
NOTE
Dimension ‘Y’ is measured from the end of the
terminal to the end of the outer (100mm) pipe.
The internal trim should be fitted to the flue pipe
before connection of the 90º bend.
10
EXTENDING THE HORIZONTAL FLUE
If the horizontal flue requires extension/s or
additional bend/s, the standard horizontal flue
terminal (2359029) must be used. Connect the
bend – supplied with the terminal kit – to the top of
the boiler using the clips, screws, & gaskets
supplied. The additional bends & extensions have
an internal push-fit connection, care should be
taken to ensure that the correct seal is made when
assembling the flue system. Connect the required
number of flue extensions or bends (up to the
maximum equivalent flue length) to the flue terminal
using the clips, screws, & gaskets supplied (see
fig. 8A & 8B).
Push-fit
connection
Extension
7,5 mm
Boiler
Fig. 8B
Mynute
SECTION 4: INSTALLATION
Insert the flue restrictor ring into the appliance
flue outlet (see fig. 1), if the total flue length –
including the allowance for any additional bends
– does not exceed 1.0 metre.
Connect the vertical flue assembly to the boiler
flue spigot using the 60mm & 100mm clips, gaskets,
& screws (supplied), ensuring the correct seal is
made. The flue support bracket (supplied with the
vertical flue kit) can now be fitted.
If the vertical flue requires extension/s or additional
bend/s, connect the required number of flue
extensions or bends (up to the maximum equivalent
flue length) between the boiler and vertical flue.
NOTE
When cutting the horizontal flue terminal or an
extension to the required length, you must ensure
that the excess is cut from the plain end of the
terminal or extension, and that the inner (60mm)
pipe is 7.5mm longer than outer (100mm) pipe
(see fig. 8A & 8B). Remove any burrs, and check
that any seals are located properly.
You must ensure that the entire flue system is
properly supported and connected.
Seal the flue assembly to the wall using cement or
a suitable alternative that will provide satisfactory
weatherproofing. The interior and exterior trim
can now be fitted.
NOTE
When cutting an extension to the required length,
you must ensure that the excess is cut from the
plain end of the extension and that the inner
(60mm) pipe is 7.5mm longer than outer (100mm)
pipe (see fig. 8B). Remove any burrs, and check
that any seals are located properly.
You must ensure that the entire flue system is
properly supported and connected.
4.5.2 CONCENTRIC VERTICAL FLUE
The vertical flue terminal can be connected directly
to the appliance flue outlet. Alternatively, an
extension or bend can be connected to the
appliance flue outlet if desired (see 4.4.2), however
if additional bends are fitted, a reduction must be
made to the maximum flue length (see table
below).
300 mm minimum
Reduction for bends
Bend
45º bend
90º bend
Reduction in maximum flue length for
each bend
0.5 metre
1.0 metre
465 mm
Vertical flue terminal and accessories
Part No.
Description
Length
2359039
Vertical flue terminal
1.0 metre
0225770
Pitched roof flashing
plate
N/A
0225765
Flat roof flashing plate
N/A
2359069
750mm extension
750mm
2359079
1500mm extension
1500mm
2359049
45º bend (pair)
N/A
2359059
90º bend
N/A
0225760
Wall bracket (5)
N/A
Using the dimensions given in fig. 9 as a reference,
mark and cut a 105mm hole in the ceiling and/or
roof.
Fit the appropriate flashing plate to the roof and
insert the vertical flue terminal through the flashing
plate from the outside, ensuring that the collar on
the flue terminal fits over the flashing.
The fixing holes for the wall-mounting bracket
should now be drilled and plugged, an appropriate
type and quantity of fixing should be used to
ensure that the bracket is mounted securely.
Once the bracket has been secured to the wall,
mount the appliance onto the bracket.
IMPORTANT
The vertical flue terminal is 1.0 metre in length and
cannot be cut; therefore it may be necessary to
adjust the height of the appliance to suit or use a
suitable extension.
Mynute
Fig. 9
4.5.3
190 mm
TWIN FLUE SYSTEM
The Vokera twin flue system enables greater flue
distances to be achieved (see 2.8) than that of
the standard concentric flue system. It can be
used for horizontal or vertical applications,
however the twin flue system must be converted
to the dedicated concentric flue kit for termination.
It is essential that the installation of the twin flue
system be carried out in strict accordance with
these instructions.
11
SECTION 4: INSTALLATION
GUIDANCE NOTES ON TWIN FLUE INSTALLATION
● The flue must have a fall back of 1º back to the
appliance to allow any condensate that may
form in the flue system to drain via the
condensate drain. Consideration must also be
given to the fact that there is the possibility of a
small amount of condensate dripping from the
terminal.
● Ensure that the entire flue system is adequately
supported, use at least one bracket for each
extension.
● The entire flue system must be adequately
insulated to maintain heat within the flue system
thereby reducing the possibility of condensate
production.
● As the exhaust outlet pipe can reach very high
temperatures it must be protected to prevent
persons touching the hot surface.
Bend
45º bend
90º bend
Reduction in maximum flue length for
each bend
1.0 metre
1.0 metre
Twin flue accessories
Part No. Description
0225805 Horizontal flue terminal
0225810 Vertical flue terminal
300
Twin adapter kit
0225770 Pitched roof flashing plate
0225765 Flat roof flashing plate
0225815 Condensate drain kit
0225820 0.25m extension (pair)
0225825 0.5m extension (pair)
0225830 1.0m extension (pair)
0225835 2.0m extension (pair)
0225840 45º bend (pair)
0225845 90º bend (pair)
0225850 Twin bracket (5)
0225855 Single bracket (5)
Length
1.0 metre
1.0 metre
N/A
N/A
N/A
N/A
250mm
500mm
1000mm
2000mm
N/A
N/A
N/A
N/A
MOUNTING THE BOILER
The fixing holes for the wall-mounting bracket
should now be drilled and plugged, an
appropriate type and quantity of fixing should be
used to ensure that the bracket is mounted
securely. Once the bracket has been secured to
the wall, mount the appliance onto the bracket.
4.5.3.1 INSTALLATION OF TWIN ADAPTOR KIT (fig. 10)
● Insert the restrictor ring (supplied with the
instruction pack) if the total flue length –
including the allowance for any bends – is less
than 5 metres (for 12e) and 7 metres (for 16e
& 20e).
● Insert the exhaust connection manifold onto the
appliance flue outlet.
● Place the silicone seal (supplied with twin
adapter kit) over the rim of the exhaust
connection manifold.
12
●
Remove the blanking plate (located to the left
of the appliance flue outlet) and – using the
same screws – install the air baffle.
Fig. 10
Condensate drain kit
Fig. 11
4.5.3.2 INSTALLATION OF CONDENSATE DRAIN KIT
(fig. 11)
The condensate drain kit must be fitted within 1
metre of the appliance flue outlet. It is
recommended that the condensate drain kit
should be fitted in the vertical plane, however it
can be fitted horizontally with care.
● Fit the first bend to the condensate drain kit or
exhaust connection manifold by firmly pushing
in to position.
● Using the two holes in the exhaust connection
manifold as a guide, drill a 3mm hole in each
and secure using the screws provided.
● Connect the air inlet pipe to the air baffle as
above.
● The twin flue pipes extensions and accessories
can now be installed by pushing together (the
plain end of each extension or bend should be
pushed approximately 50mm into the female
socket of the previous piece).
The condensate drain trap must be connected
to the drain in accordance with building
Regulations or other rules in force.
Mynute
SECTION 4: INSTALLATION
4.5.3.3 HORIZONTAL TERMINATION (See fig. 12)
The twin flue system must be converted to the
dedicated concentric flue kit for termination.
● The horizontal terminal is supplied with a builtin converter box and cannot be shortened.
● A 130mm hole is required for the passage of
the concentric terminal through the wall.
Depending on site conditions it may be preferable
to install the terminal assembly prior to fitting the
twin flue pipes.
Mark and drill a 130mm hole for the passage of
the horizontal flue terminal, ensuring that there
is a 1º fall back to the boiler (17mm per 1000mm).
Insert the terminal assembly into the flue hole.
Push-fit the twin flue pipes onto the concentric to
twin converter box ensuring that the exhaust pipe
connects to the exhaust connection on the
concentric to twin converter.
If necessary cut the plain ends (male) of the twin
flue pipes to allow connection to the concentric
to twin converter.
NOTE
Before cutting twin flue pipes ensure allowances
have been made for connection onto the previous
piece and onto the concentric to twin converter.
The last twin flue pipes must be pushed 50mm
onto the male sockets of the concentric to twin
converter.
NOTE
You must ensure that the entire flue system is
properly supported and connected.
Seal the flue terminal assembly to the wall using
cement or a suitable alternative that will provide
satisfactory weatherproofing.
The interior and exterior trim can now be fitted.
The converter box must be removed whilst
inserting the vertical flue terminal through the
flashing plate.
4.5.3.4 VERTICAL TERMINATION (See fig. 13)
The twin flue system must be converted to the
dedicated concentric flue kit for termination.
● The vertical terminal is supplied with a built-in
converter box and cannot be shortened.
● A 130mm hole is required for the passage of
the concentric terminal through the ceiling and/
or roof.
Depending on site conditions it may be preferable
to install the terminal assembly prior to fitting the
twin flue pipes.
Fit the appropriate flashing plate to the roof and
insert the vertical flue terminal through the
flashing plate from the outside, ensuring that the
collar on the flue terminal fits over the flashing.
Push-fit the twin flue pipes onto the concentric to
twin converter ensuring that the exhaust pipe
connects to the exhaust connection on the
concentric to twin converter.
If necessary cut the plain ends (male) of the twin
flue pipes to allow connection to the concentric
to twin converter.
NOTE
Before cutting twin flue pipes ensure allowances have
been made for connection onto the previous piece
and onto the concentric to twin converter. The last
twin flue pipes must be pushed 50mm onto the male
spigots of the concentric to twin converter.
●
You must ensure that the entire flue system is
properly supported and connected.
●
Ensure that any horizontal sections of pipe have a
1º fall towards the appliance (17mm per 1000mm).
●
Fig. 13
Vertical roof outlet
Fig. 12
Twin Flue Convertor Box
Twin flue Convertor Box
Condensate Drain Kit
Horizontal Concentric
Terminal
Mynute
Condensate Drain Kit
13
SECTION 4: INSTALLATION
4.6
CONNECTING THE GAS AND WATER
The appliance is supplied with an accessories pack
that contains sealing washers and service valves.
The service valves are of the compression type.
When connecting pipe work to the valves, tighten
the compression end first then insert the sealing
washers before tightening the valve to the
appliance.
NOTE
It will be necessary to hold the valve with one
spanner whilst tightening with another.
4.6.1
GAS (fig. 6)
The appliance is supplied with a 15mm service
valve, connect a 15mm pipe to the inlet of the
valve and tighten both nuts.
NOTE
It will be necessary to calculate the diameter of
the gas supply pipe to ensure the appliance has
an adequate supply of gas.
4.6.2
FLOW & RETURN (fig. 6)
The appliance is supplied with 22mm service
valves for the flow and return connections,
connect a 22mm pipe to the inlet of each valve
and tighten both nuts.
4.6.3
SAFETY VALVE (fig. 1)
Connect a suitable coupling and 15mm pipe to
the safety valve outlet and tighten. The discharge
pipe must have a continuos fall away from the
appliance to outside and allow any water to drain
away thereby eliminating the possibility of
freezing. The discharge pipe must terminate in a
position where any water – possibly boiling –
discharges safely without causing damage or
injury, but is still visible.
4.7
ELECTRICAL CONNECTIONS
The electrical supply must be as specified in 3.7.
A qualified electrician should connect the
electrical supply to the appliance. If controls –
external to the appliance – are required, a
competent person must undertake the design of
any external electrical circuits, please refer to
section 8 for detailed instructions. ANY
EXTERNAL CONTROL OR WIRING MUST BE
SERVED FROM THE SAME ISOLATOR AS
THAT OF THE APPLIANCE. The supply cable
from the isolator to the appliance must be 3-core
flexible sized 0.75mm to BS 6500. Wiring to the
appliance must be rated for operation in contact
with surfaces up to 90°C.
4.7.1
14
CASING REMOVAL
To gain access to the appliance electrical
connections you must first remove the casing,
proceed as follows:
● locate and remove the 2 screws that secure
the controls fascia to the appliance casing (see
fig 14);
● gently lower the control fascia until it rests;
casing screws
Fig. 14
terminal block
cover
Fig. 14a
gently pull one side of the casing then the other
to disengage it from the retaining clips;
● lift the casing upward to disengage it from the
top locating hooks and then remove;
● store the casing and screws safely until
required.
Re-fit in the reverse order.
●
4.7.2
APPLIANCE TERMINAL BLOCK
The appliance terminal block is located on the
left side of the control fascia (see fig. 14a). Locate and remove the screws securing the terminal block cover.
NOTE
The appliance comes with a factory fitted link to
allow basic operation of the boiler via the mode
selector switch. If it is anticipated that external
controls will be required please refer to the wiring
diagrams in section 8 for more detailed
information.
Mynute
SECTION 4: INSTALLATION
4.7.3
Do not remove the link wire (1 - 2) unless additional external controls are to be fitted (see section 8). Re-fit the appliance terminal block cover.
The securing screw on the cable anchorage
should now be tightened. This must be done
before the control fascia is re-fitted in the upright
position. The appliance casing and screws can
now be re-fitted.
CONNECTING THE MAINS (230V) INPUT (see
fig. 16)
Remove the terminal block cover as described
in 4.7.2. Pass the cable through the cable anchorage (see fig. 15).
On the terminal block there are 9 terminals from
left to right they are:
● EARTH
● LIVE
● NEUTRAL
● 1
● 2
● 3
● 4
● 5
● 6
Connect the supply cable wires (earth, live, and
neutral) to their corresponding terminals on the
appliance terminal block. Ensure that the EARTH
wire is left slightly longer that the others, this will
prevent strain on the earth wire should the cable
become taut.
cable entry
view beneath boiler
Fig. 15
compensator tube
Outlet test nipple
Protective cap
N
E
Inlet test nipple
L
Fig. 16
Fig. 17
2
1
4
3
6
5
Natural gas
14
Burner pressure (mbar)
12
20e
10
8
16e
e
12
6
4
2
0
7
8
9
10
11
12
13
14
Output (kW)
Mynute
15
16
17
18
19
20
Fig. 17a
15
SECTION 5: COMMISSIONING
5.1
GAS SUPPLY INSTALLATION
Inspect the entire installation including the gas
meter, test for soundness and purge. Refer to BS
6891 for specific instruction.
5.2
THE HEATING SYSTEM
The appliance contains components that may
become damaged or rendered inoperable by oils
and/or debris that are residual from the
installation of the system, consequently it is
essential that the system be flushed in
accordance with the following instructions.
5.3
5.4
5.5
16
INITIAL FILLING OF THE SYSTEM
Ensure both flow and return service valves are
open, remove appliance casing as described in
4.7.1, identify the automatic air release valve and
loosen the dust cap by turning the cap anticlockwise one full turn. IMPORTANT, THERE
ARE NO MANUAL AIR RELEASE VALVES
LOCATED ON THE APPLIANCE. Ensure all
manual air release valves located on the heating
system are closed. Using the method of filling as
described in fig. 5, slowly proceed to fill the
system. As water enters the system the pressure
gauge will begin to rise. Once the gauge has
reached 1 bar close the filling valve and begin
venting all manual air release valves, starting at
the lowest first. It may be necessary to go back
and top-up the pressure until the entire system
has been filled. Inspect the system for water
soundness, rectifying any leaks.
INITIAL FLUSHING
The whole of the heating system must be flushed
both cold and hot as detailed in 5.8. Open all
radiator or heating valves and the appliance flow
& return service valves. Drain the boiler and
system from the lowest points. Open the drain
valve full bore to remove any installation debris
from the boiler prior to lighting. Refill the boiler
and heating system as described in 5.3.
PRE-OPERATION CHECKS
Before attempting the initial lighting of the
appliance, the following checks must be carried
out:
● ensure all gas service valves from the meter to
the appliance are open and the supply pipe has
been properly purged;
● ensure the proper electrical checks have been
carried out, (see 7.7) particularly continuity,
polarity, and resistance to earth;
● ensure the 3 amp fuse – supplied with the
appliance – has been fitted;
● ensure the system has been filled, vented, and
the pressure set to 1 bar;
● ensure the flue system has been fitted properly
and in accordance with the instructions;
● ensure all appliance service valves are open.
5.6
INITIAL LIGHTING
Ensure the electrical supply to the appliance is
switched on. Switch the time clock or programmer
to an ‘on’ position and ensure all external controls
are also calling for heat. Turn the mode selector
switch to the ‘on’ position (fig. 1).
The appliance will now go through an ignition
sequence as described in 1.2. Should the
appliance fail to ignite, refer to 5.5 and/or section
7 (fault finding).
5.7
CHECKING THE BURNER PRESSURE
Although the burner pressure is factory set, it is
necessary to check it during commissioning.
Isolate the appliance from the electrical supply
and attach a suitable manometer to the gas valve
outlet test nipple (see fig. 17). Light the boiler as
described in 5.6 and compare the reading on the
manometer with the value described in 2.2. If
adjustment is required, follow the detailed
instructions in section 7 (7.3).
Once the burner pressure has been checked,
isolate the appliance from the electrical supply,
remove the manometer, and tighten the gas valve
outlet test nipple.
5.8
FINAL FLUSHING OF THE HEATING SYSTEM
The system should be flushed in accordance with
BS 7593. Turn on the boiler for central heating
and hot water and allow the boiler to reach
temperature. Turn off the boiler and drain the
system whilst still hot.
Refill the boiler and system as described in 5.3.
Although not necessary for the correct operation
of the boiler, an inhibitor may be added at this
point. Contact the inhibitor manufacturer for
further information regarding application and
dosage.
5.9
SETTING THE BOILER OPERATING
TEMPERATURE
The flow outlet temperature can be adjusted
between 40°C - 80°C via the thermostat knob
(see fig.1).
5.10
SETTING THE SYSTEM DESIGN PRESSURE
The design pressure should be a minimum of 1
bar and a maximum of 1.5 bar.
The actual reading should ideally be 1bar plus
the equivalent height in metres (0.1 bar = 1 metre)
to the highest point in the system above the base
of the appliance (up to the maximum of 1.5 bar
total).
N.B. The safety valve is set to lift at 3 bar/30
metres/45 psig.
To lower the system pressure to the required
value, pull lever on head of safety valve to release
water until the required figure registers on the
pressure gauge (see fig. 1).
Mynute
SECTION 5: COMMISSIONING
5.11
5.12
REGULATING THE CENTRAL HEATING
SYSTEM
Fully open all radiator and circuit valves and run
the appliance for both heating and hot water until
heated water is circulating. If conditions are warm
remove any thermostatic heads. Adjust radiator
return valves and any branch circuit return valves
until the individual return temperatures are correct
and are approximately equal.
FINAL CHECKS
ENSURE ALL TEST NIPPLES ON THE
APPLIANCE GAS VALVE HAVE BEEN
TIGHTENED AND CHECKED FOR
SOUNDNESS.
● ENSURE THE APPLIANCE FLUE SYSTEM IS
FITTED CORRECTLY AND IS PROPERLY
SECURED.
● ENSURE ALL PIPE WORK IS RE-CHECKED
FOR SOUNDNESS.
● RE-FIT APPLIANCE CASING.
● COMPLETE APPLIANCE LOGBOOK.
Complete details of the boiler, controls,
installation, and commissioning in the logbook
supplied with the boiler. This is an important
document, which must be correctly completed
and handed to the user. Failure to install and
commission the appliance to the manufacturers
instructions may invalidate the warranty.
●
5.13
INSTRUCTING THE USER
Hand over all documentation supplied with this
appliance – including these instructions – and
explain the importance of keeping them in a safe
place.
Explain to the user how to isolate the appliance
from the gas, water, and electricity supplies, and
the locations of all drain points.
Show the user how to operate the appliance and
its associated controls correctly.
Show the user the location of the filling valve and
how to top-up the system pressure correctly, and
show the location of all manual air release points.
Explain to the user how to turn off the appliance
for both long and short periods and advise on
the necessary precautions to prevent frost
damage.
Explain to the user that for continued safe and
efficient operation, the appliance must be
serviced annually by a competent person.
Mynute
17
SECTION 6: SERVICING
6.1
GENERAL
To ensure the continued safe and efficient
operation of the appliance, it is recommended
that it is checked and serviced at regular intervals.
6.4
COMPONENT REMOVAL PROCEDURE
To remove a component, access to the interior of
the appliance is essential. Isolate the appliance
from the electrical supply and remove the fuse.
And when necessary, close all service valves on
the appliance, remove the appliance casing as
described in section 4.7.1, drain the water content
from the appliance via the safety valve. Ensure
some water absorbent cloths are available to
catch any residual water that may drip from the
appliance or removed component. Undertake a
complete commissioning check as detailed in
section 5, after replacing any component.
ALWAYS TEST FOR GAS SOUNDNESS IF
ANY GAS CARRYING COMPONENTS HAVE
BEEN REMOVED OR DISTURBED.
6.5
PUMP HEAD (see fig. 18)
Carry out component removal procedure as
described in 6.4.
Using a 4mm Allen key or ‘T’ bar, unscrew and
remove the four Allen screws that hold the pump
in position, pull firmly on the pump head to
release it from the base. Disconnect the electrical
leads. Replace in the reverse order.
6.6
SAFETY VALVE (see fig. 18)
Carry out component removal procedure as
described in 6.4.
Disconnect the outlet pipe from the safety valve,
unscrew and remove the hex bush from the
safety valve outlet, remove safety valve locking
pin from appliance manifold. Replace in the
reverse order
The frequency of servicing will depend upon the
particular installation conditions, but in general,
once per year should be adequate.
It is the law that any servicing work is carried out
by competent person such as a Vokera engineer,
an approved service agent, British Gas, or other
CORGI registered personnel.
The following instructions apply to the appliance
and its controls, but it should be remembered that
the central heating and the domestic hot water
systems will also require attention from time to
time.
6.2
ROUTINE ANNUAL SERVICING
Check the operation of the appliance and ensure
it functions as described in section 7. Compare
the performance of the appliance with its design
specification. The cause of any noticeable
deterioration should be identified and rectified
without delay.
Thoroughly inspect the appliance for signs of
damage or deterioration especially the flue system
and the electrical apparatus.
Check and adjust – if necessary – all burner
pressure settings. (See 7.3)
Check and adjust – if necessary – the system
design pressure. (See 5.10)
Carry out an analysis of the flue gases (see 7.4),
and visually check the condition of the entire flue
assembly. Compare the results with the appliance
design specification. Any deterioration in
performance must be identified and rectified
without delay.
Pump
Ensure both flue venturis are clean and free from
any debris or obstruction.
Ensure both the burner and heat exchanger are
clean and free from any debris or obstruction.
Inspect all joints for signs of leakage and repair if
necessary.
Refer to the commissioning section and/or
replacement of parts section for detailed
instruction if required.
6.3
18
REPLACEMENT OF COMPONENTS
Although it is anticipated that this appliance will
give years of reliable, trouble free service, the life
span of components will be determined by factors
such as operating conditions and usage. Should
the appliance develop a fault, the fault finding
section will assist in determining which component
is malfunctioning.
fig. 18
6.7
Safety valve
AUTOMATIC AIR RELEASE VALVE (see fig.
18) (AAV)
Carry out component removal procedure as
described in 6.4.
Remove the locking pins from both the pressure
gauge and expansion pipe connections from the
pump base. Remove both the pressure gauge
phial and expansion pipe from the pump base.
Using a suitable pair of pump pliers, unscrew the
AAV from the pump base. Replace in the reverse
order.
Mynute
SECTION 6: SERVICING
6.8
WATER PRESSURE SWITCH (see fig. 19)
Carry out component removal procedure as
described in 6.4.
Remove locking pin and the water pressure switch
from the heating manifold, and – after taking note
of the electrical connections – disconnect the
wiring. Replace in the reverse order.
6.11
HIGH LIMIT THERMOSTAT (see fig. 20)
Carry out component removal procedure as
described in 6.4.
Pull off electrical connections from the high limit
thermostat, slacken and remove retaining screws.
Replace in reverse order.
6.12
PRINTED CIRCUIT BOARD (PCB)
Carry out component removal procedure as
described in 6.4.
Locate and remove the five screws which secure
the PCB cover & terminal cover, then remove
cover, after carefully taking note of all wiring
connections, disconnect all wiring from the PCB,
locate and remove the PCB securing screws,
remove PCB. Replace in the reverse order.
6.13
GAS VALVE (see fig. 21)
Carry out component removal procedure as
described in 6.4.
The gas valve must be changed as complete unit.
Disconnect the electrical plug from the gas valve.
Disconnect silicone tube from gas valve regulator.
Slacken and unscrew gas valve inlet and outlet
connections. Please note, the sealing washers
must be discarded and replaced with new sealing
washers. Locate and remove gas valve retaining
screws on the underside of the boiler, the gas
valve can now be removed. Replace in the reverse
order. Check and adjust burner pressure settings.
WARNING, A GAS SOUNDNESS CHECK
MUST BE CARRIED OUT.
fig. 19
6.9
6.10
PRESSURE GAUGE
Carry out component removal procedure as
described in 6.4.
Remove pressure gauge locking pin, located on
pump base, and withdraw the pressure gauge
pipe, locate the spring tabs on the pressure
gauge body, push and hold tabs in, to enable
extraction of the gauge from its location. Replace
in the reverse order.
outlet test nipple
NTC THERMISTOR (see fig. 20)
Carry out component removal procedure as
described in 6.4.
Disconnect thermistor electrical plug. Using a
13mm spanner slacken and remove the thermistor
and sealing washer. Replace in the reverse order.
burner pressure
adjusting screw
inlet test nipple
fig. 21
6.14
fig. 20
Mynute
supply plug
INTEGRAL TIME SWITCH (if fitted)
Carry out component removal procedure as
described in 6.4.
Locate and remove the terminal cover and
securing screws (2), locate and remove the time
clock retaining screws, remove time clock.
Disconnect wiring after carefully taking note of all
electrical connections. Replace in the reverse
order.
19
SECTION 6: SERVICING
6.15
BURNER, INJECTORS AND SPARK/SENSE
ELECTRODE (see fig. 22 & 22a)
Carry out component removal procedure as
described in 6.4.
Locate and remove the air chamber cover (held
by 6 screws). Locate and remove the 6 screws
securing the front combustion cover, pull the
cover towards you before lifting and disengaging.
Disconnect the electrode lead from its connector
at the rear of the boiler. Locate and remove the
four screws which secure the burner in position,
gently ease the burner out of its location whilst
also easing the electrode sealing grommet from
its seating. Once the burner has been removed,
locate the burner injectors – located to the rear of
the combustion chamber – and remove (if
necessary). Replace in the reverse order. Please
note, the injector sealing washers must be
replaced if the injectors have been removed,
ensure all seals are in good condition, taking care
to ensure they are replaced correctly.
fig. 22
6.16
FLUE FAN (see fig. 23)
Carry out component removal procedure as
described in 6.4.
Remove the air chamber cover by un-screwing
the six screws which hold the cover, gently pull
the cover towards you before lifting and
disengaging. Locate and remove the six screws
that secure the front combustion cover, then
remove the cover. Disconnect the electrical
connections and silicone tubes attached to the
fan, noting their positions. Locate and remove the
three screws that secure the flue hood, ease the
fan & flue hood assembly from its location. Locate
and remove the four screws that secure the fan to
the flue hood. Replace in the reverse order.
Ensure all seals are in good condition, taking care
to ensure they are replaced correctly
fig. 23
6.17
HEAT EXCHANGER (see fig. 24)
Carry out component removal procedure as
described in 6.4.
Remove the air chamber cover by un-screwing
the six screws which hold the cover, gently pull
the cover towards you before lifting and
disengaging. Locate and remove the six screws
that secure the front combustion cover, then
remove the cover. Disconnect the flow and return
connections on the heat exchanger. The heat
exchanger can now be withdrawn from the
appliance. Replace in the reverse order. Ensure
all seals are in good condition, taking care to
ensure they are replaced correctly.
fig. 22a
20
Mynute
SECTION 6: SERVICING
fig. 24
6.18
AIR PRESSURE SWITCH (see fig. 1)
Carry out component removal procedure as
described in 6.4.
Remove the air chamber cover by un-screwing
the six screws which hold the cover, gently pull
the cover towards you before lifting and
disengaging. Locate and remove the two screws
holding the air pressure switch to the air chamber.
Disconnect the electrical connections and silicone
tubes attached to the air pressure switch, noting
their positions. Replace in the reverse order.
Ensure all seals are in good condition, taking care
to ensure they are replaced correctly.
6.19
EXPANSION VESSEL (see fig. 1)
Due to the compact design of this appliance,
removal and/or replacement of the expansion
vessel may require the appliance to be removed
from the wall, if this is deemed impractical, an
external expansion vessel may be fitted to the
return pipe as close to the appliance as possible.
6.19.1 EXPANSION VESSEL (removal)
Carry out component removal procedure as
described in 6.4.
Disconnect the flue from the appliance.
Disconnect the expansion pipe from the vessel,
slacken and remove the locknut that secures the
lower part of the vessel to the appliance frame.
Locate and remove the six screws that secure the
vessel top holding plate, remove the plate. The
expansion vessel can now be removed. Replace
in the reverse order. Ensure all seals are in good
condition, taking care to ensure they are replaced
correctly.
Mynute
21
SECTION 7: CHECKS, ADJUSTMENTS & FAULT FINDING
7.1
7.2
CHECKING APPLIANCE OPERATION
When carrying out any repairs or servicing to the
appliance, the relevant commissioning procedure
must be undertaken to ensure the continued safe
operation of the appliance. Particular attention
should be made to ensure gas soundness, water
soundness, and the electrical integrity of the
appliance.
APPLIANCE MODE OF OPERATION
When there is a request for heat and/or hot water
via the programmer/time clock and/or any external
control, the pump and fan are started.
NOTE
There must be sufficient system water pressure
(min. 0.5 bar) to ensure the water pressure switch
is activated. If there is insufficient system pressure
the pump and fan will be prevented from operating.
When the fan runs, it proves the differential air
pressure switch which in-turn allows an ignition
sequence to begin.
NOTE
The ignition sequence lasts approximately 5
seconds, during which the appliance will continue
to spark even if the burner has already lit.
If the spark/sensing electrode does not sense
ignition the appliance will then go to lockout.
Ignition is sensed by the electronic circuitry to
ensure flame stability at the burner. Once
successful ignition has been achieved, the
electronic circuitry allows full gas rate through the
appliance.
When the appliance reaches the desired
temperature the burner will shut down and the
boiler will perform a three-minute anti-cycle (timer
delay).
NOTE
The timer delay can be de-activated by the
insertion of a ‘jumper’ on the PCB or by isolating
the appliance from the electrical supply from 30
seconds.
When the request for heat and/or hot water has
been satisfied the appliance pump will continue
to circulate for a period of 30 seconds to dissipate
any residual heat within the appliance.
7.3
22
Light the boiler as described in 5.6 and compare
the reading on the manometer with the value
described in fig. 17a. If adjustment is required
remove the compensator tube from the gas valve
regulator.
Locate and remove the protective screwed cap
that covers the burner pressure adjusting screw.
Adjust the screw clockwise to increase the
pressure or anti-clockwise to reduce.
Once the pressure has been adjusted, isolate the
appliance from the electrical supply, replace the
protective screwed cap, refit the compensator
tube, remove the manometer, and tighten the
outlet test nipple.
CHECKING AND ADJUSTING BURNER PRESSURE (see fig. 17 & 17a)
Although the burner pressure is factory set, it is
necessary to check it during servicing or if the gas
valve has been removed.
Isolate the appliance from the electrical supply
and attach a suitable manometer to the gas valve
outlet test nipple.
IMPORTANT, A GAS SOUNDNESS CHECK
MUST BE CARRIED OUT.
7.4
COMBUSTION ANALYSIS TEST
A combustion analysis check can easily be
carried out on the appliance via the test points
located on the top of the appliance, however
you must check that the burner pressure is set
at maximum (see 7.3).
12e
16e
20e
CO
50 ppm
55 ppm
160 ppm
CO2
6.70%
6.15%
6.0%
7.5
CHECKING THE EXPANSION VESSEL
Carry out the component removal procedure as
described in 6.4. You must ensure that the boiler
is completely drained of water.
Using a suitable pressure gauge, remove dust
cap on expansion vessel and check the charge
pressure. The correct charge pressure should be
0.8 bar ± 0.1 bar.
If the charge pressure is less, use a suitable
pump to increase the charge.
Please note, you must ensure the safety valve is
in the open position whilst re-charging takes
place. Replace the dust cap and carry out the
relevant commissioning procedure (section 5).
Mynute
SECTION 7: CHECKS, ADJUSTMENTS & FAULT FINDING
7.6
EXTERNAL FAULTS
Before carrying out any fault finding or component
replacement, ensure the fault is not attributable to
any aspect of the installation.
For example, external wiring fault, service valves
closed, reversed polarity, gas supply turned off,
etc.
7.6.1
INSTALLATION FAULTS
FAULT
POSSIBLE CAUSES
REMEDY/ACTION
Appliance fires then lockouts
Incorrect gas pressure
Flue blocked or broken
Check incoming gas supply
Inspect flue system
Appliance wont fire
External wiring fault
Disconnect external wiring and
fit link between 1 & 2
Ensure pressure gauge is
above 0.5 BAR
Check and replace
Check wiring and or
disconnect external wiring
Insufficient system pressure
Appliance stays fired after time
clock/programmer has
switched off
Appliance fires but no
circulation
Blown fuse
External wiring fault
Faulty motorised valve
Service valves closed
Defective motorised valve
Defective external wiring
Air in system/boiler
7.7
ELECTRICAL CHECKS
Any electrical checks must be carried out by a
suitably qualified person.
7.7.1
EARTH CONTINUITY TEST
Isolate the appliance from the electrical supply,
and using a suitable multi-meter carry out a
resistance test. Connect test leads between an
appliance earth point and the earth wire of the
appliance supply cable. The resistance should
be less than 1 ohm. If the resistance is greater
than 1 ohm check all earth wires and connectors
for continuity and integrity.
7.7.2
7.7.3
SHORT CIRCUIT CHECK
Isolate the appliance from the electrical supply,
and using a suitable multi-meter, carry out a short
circuit test between the Live & Neutral connections
at the appliance terminal strip (fig.16).
Repeat above test on the Live & Earth connections
at the appliance terminal strip (fig.16).
NOTE
Should it be found that the fuse has failed but no
fault is indicated, a detailed continuity.
Check will be required to trace the fault. A visual
inspection of components may also assist in
locating the fault.
POLARITY CHECK
With the appliance connected to the electrical
supply and using a suitable multimeter, carry out
the following voltage tests:
● connect test leads between the Live & Neutral
connections at the appliance terminal strip
(fig.16), the meter should read approximately
230V ac. If so proceed to next stage. If not, see
7.7.4.
Mynute
Open service valves!
Check operation
Check wiring
Check dust cap on AAV
Vent system & radiators
●
●
connect test leads between the Live & Earth
connections at the appliance terminal strip
(fig.16), the meter should read approximately
230V ac. If so proceed to next stage. If not, see
7.7.4.
connect test leads between the Neutral & Earth
connections at the appliance terminal strip
(fig.16), the meter should read approximately 0
– 15Vac. If so polarity is correct. If not, see
7.7.4.
7.7.4
REVERSED POLARITY OR SUPPLY FAULT
Repeat the above tests at the appliance isolator,
if testing reveals correct polarity and/or supply at
the isolator, re-check wiring and connections
between the isolator and the appliance.
If tests on the isolator also reveal reversed polarity
or a supply fault, consult the local electricity
supplier for advice.
7.7.5
RESISTANCE TO EARTH CHECK
Isolate the appliance from the electrical supply,
and using a suitable multi-meter carry out a
resistance test. Connect test leads between the
Live & Earth connections at the appliance terminal
strip (fig.9a). If the meter reads other than infinity
there is a fault that must be isolated, carry out a
detailed continuity check to identify the location of
the fault.
IMPORTANT
These series of checks must be carried out
before attempting any fault finding procedures on
the appliance. On completion of any task that
required the disconnection and re-connection of
any electrical wiring or component, these checks
must be repeated.
23
SECTION 7: CHECKS, ADJUSTMENTS & FAULT FINDING
THE FOLLOWING CHECKS MUST BE CARRIED OUT
BEFORE ATTEMPTING ANY INTERNAL FAULT
FINDING:
● Ensure system pressure is 0.5 bar or above
● Carry out routine electrical checks
● Disconnect external controls from appliance and insert
link-wire between terminals 1 & 2
● Fit ‘jumper’ to JP1 to cancel timer delay if necessary
● Turn boiler thermostat to maximum
● Reset boiler mode switch if required
IF THE BOILER WILL NOT RESET CHECK THE
FOLLOWING:
● Resistance of NTC thermistor and/or continuity of
wiring
● Continuity through mode selector switch
● PCB
INITIAL ELECTRICAL CHECK
24
Mynute
SECTION 7: CHECKS, ADJUSTMENTS & FAULT FINDING
TEST “A”
TEST “B”
TEST “C”
Mynute
25
SECTION 8: WIRING DIAGRAMS
8.1 “Y” PLAN USING AN EXTERNAL DIAGRAMS
Appliance Terminal Strip
230V Supply @ 50Hz
Earth
Live
Neutral
Calling
Satisfied
3 AMP Fuse
Common
Cylinder Thermostat
Load
Wiring Centre or
Junction Box
Live
3-Port Motorised Valve
Room
Thermostat
Blue
Green/Yellow
Grey
Orange
Heating
Off
On
Hot water
Off
On
White
Twin Channel Programmer
8.2 “S” PLAN USING EXTERNAL DIAGRAMS
Appliance Terminal Strip
Room Thermostat
Cylinder Thermostat
Load
Load
Live
Common
Wiring Centre or Junction Box
E
L
N
Motorised Valve (hot water)
3 AMP Fuse
Orange
Grey
Twin Channel Programmer
Heating
Off
On
Hot water
Off
On
Brown
Blue
Green/Yellow
Orange
Grey
Brown
Blue
Green/Yellow
Motorised Valve (heating)
26
Mynute
SECTION 8: WIRING DIAGRAMS
8.3 “Y” PLAN WITH VOKERA TWIN CHANNEL PROGRAMMER (see 8.6 for instructions)
Vokera Twin Channel Programmer
HW On
HW Off
Heating On
Heating Off
Live Supply
Neutral
230V Supply
Appliance Terminal Strip
E
L
N
3 AMP Fuse
Wiring Centre or Junction Box
Satisfied
Calling
Common
Cylinder Thermostat
Load
Live
3-Port Motorised Valve
Grey
Orange
White
Blue
Green/Yellow
Room Thermostat
8.4 “S” PLAN WITH VOKERA TWIN CHANNEL PROGRAMMER (see 8.6 for instructions)
Vokera Twin Channel Programmer
HW On
HW Off
Heating On
Heating Off
Live Supply
Neutral
230V Supply
Appliance Terminal Strip
E
L
N
Wiring Centre or
Junction Box
3 AMP Fuse
Room Thermostat
Load
Live
Calling
Common
Heating
Motorised Valve
Mynute
grey
brown
orange
green/yellow
blue
grey
brown
orange
green/yellow
blue
Cylinder Thermostat
Hot Water
Motorised Valve
27
SECTION 8: WIRING DIAGRAMS
8.5
INSTALLATION OF VOKERA TIME CLOCK (24
hour & 7 day versions).
● Isolate the appliance from the electrical supply
and remove the casing as described in 4.7.1.
● Remove the circular blanking disc from the
clock aperture plate.
● Remove the terminal strip cover from the
appliance.
● Connect the wires to the clock as shown in
fig.24.
● Mount the clock to the clock aperture plate
using the screws provided.
● Remove the factory fitted link between
terminals 1 & 2 on the appliance terminal strip.
● Connect the clock wires to the appliance
terminal strip as shown in fig. 24
● Replace the terminal cover and casing once
the clock installation has been completed.
8.6
INSTALLATION OF VOKERA TWIN CHANNEL
PROGRAMMER
● Isolate the appliance from the electrical supply
and remove the casing as described in 4.7.1.
● Remove the circular blanking disc from the
clock aperture plate.
● Remove the terminal strip cover from the
appliance PCB cover.
● Remove the factory fitted link between
terminals 1 & 2 on the appliance terminal strip.
● Take the wires supplied with the programmer
and connect them as shown in fig. 25.
● Mount the clock to the clock aperture plate
using the screws provided.
● Connect any external controls as detailed in
8.3 or 8.4.
● Replace the terminal cover and casing once
the programmer installation has been
completed.
230V Supply
230V @ 50Hz Supply
red/white
blue
N 1
2 3 4
5 6
Appliance Terminal Strip
12 3 4 5
NOTE: remove link between 1 &
2 on appliance terminal block
E
Pink
Grey
Purple
Brown
Blue
Neutral
L
3 AMP Fuse
red/black
Live
E
Red
white
3 AMP Fuse
Earth
N
L
E
Vokera Twin Channel
Programmer
L
N
1 2
3
4
5
6
HW On
HW Off
Heating On
Heating Off
Live Supply
Neutral
Appliance Terminal Strip
Vokera time clock
fig. 24
NOTE
If the connection of a room thermostat is also required,
the spare terminals on the appliance terminal strip can be
used for this purpose.
fig. 25
NOTE
The appliance and integral programmer must be
connected as described in these instructions, to ensure
the safe and correct operation of this appliance.
If an external time clock is preferred, it must have ‘voltage
free connections’. This appliance requires a permanent
electrical supply.
28
Mynute
SECTION 8: WIRING DIAGRAMS
R.T.
P.S.
H.L.
S.R.
F
P
SP\SE E.
OPE
I.C.B.
B.E.B.
CR4
K3-K4
K1-K2
LD1
D.P.S.
L
N
P1
JP1
F1
Mynute
Room thermostat
Pressure switch
High limit switch
Heat thermistor
Fan
Pump
Spark\Sense electrode
Gas valve solenoids
Ignition control board
Boiler control board
Pump triac
Fan relays
Ignition relays
Led alarm (red)
Differential pressure switch
Line
Neutral
Heat control potenziometer
Timer jumper
Fuse
29
SECTION 8: WIRING DIAGRAMS
NOTE: L-N-E CONNECTION IS ADVISABLE
ROOM THERMOSTAT IS 230 V.A.C.
30
Mynute
SECTION 9: EXPLODED DIAGRAMS
Table 1
31
1
270
226
58
5
6
15
18
90
20
22
33
49
300
21
98
12
23
43
26
28
40
Table 1 Mynute 12e - 16e - 20e
KEY DESCRIPTION
Part no 12e
Part no 16e
Part no 20e
1
6
12
15
18
20
21
22
23
26
28
31
33
40
43
49
58
90
98
226
270
300
01005135
10021233
2468
10021266
10021265
10021984
10021267
2785
10021263
10023277
10021264
10020973
1978
10020966
1864
8654
5588
3478
9461
5128
10021272
10021271
01005135
10021233
2468
10021266
10021265
10021984
10021267
2785
10021263
10023281
10021264
10020973
1978
10020966
1864
8654
5588
5588
9461
5128
10021272
10021271
01005135
10021233
2468
10021266
10021265
10021984
10021267
2785
10021263
10021291
10021264
10020973
1978
10020966
1864
8654
5588
5588
9461
5128
10021272
10021271
Frame
Guard
Quick primer pressure gauge
Cover
Cover
Printed Circuit Board
Led Light Guide
Control shaft for potentiometer
Control shaft for commutator
Instrumental panel
Knob
Case
Plastic Trade Mark Label
Door panel
Push-push cover
Plastic bezel
Case clip
3A fuse
Selector switch
Edge clip
Transformer
Wiring harness
Mynute
31
SECTION 9: EXPLODED DIAGRAMS
Table 2
2
290
288
52
7
3
289
288
289
22
303
300
288
303
289
23
400
201
63
353
27
Table 2 Mynute 12e - 16e - 20e
KEY DESCRIPTION
Part no 12e
Part no 16e
Part no 20e
2
3
7
22
23
27
52
63
201
288
289
290
300
303
353
400
10022658
2044
2047
1806
10022499
1789
10021251
10021906
5026
6898
2223
2165
2222
2217
1824
10021268
10022658
2044
2047
1806
10022499
1789
10021251
10021906
5026
6898
2223
2165
2222
2217
1824
10021268
10022658
2044
2047
1806
10022499
1789
10021251
10021906
5026
6898
2223
2165
2222
2217
1824
10021268
32
Connection
Pressure switch
Heating by-pass valve
Safety valve
Connection
Heating cook
Connection
Pipe
Washer
O ring
Clip
Clip
Clip
Connection
Ogive
Wiring harness
Mynute
SECTION 9: EXPLODED DIAGRAMS
Table 3
1
200
285
8
287
202
9
200
201
7
200
6
2
10
292
288
289
290
290
3
4
289
288
290
289
Table 3 Mynute 12e - 16e - 20e
KEY DESCRIPTION
Part no 12e
Part no 16e
Part no 20e
1
2
3
4
6
7
8
9
10
200
201
202
285
287
288
289
290
292
10020839
2164
2225
0439
10021258
10021256
10021231
10021257
10021259
5023
5026
5041
8484
2258
6898
2223
2165
7999
10020839
2164
2225
0439
10021258
10021289
10021232
10021290
10021259
5023
5026
5041
8484
2258
6898
2223
2165
7999
10020839
2164
2225
0439
10021258
10021289
10021232
10021290
10021259
5023
5026
5041
8484
2258
6898
2223
2165
7999
6 lt. expansion vessel
Flexible pipe
Up 15-50 pump
Automatic air vent bottle
Pipe
Pipe
Heat exchanger
Pipe
Pipe
Washer
Washer
Washer
NTC sensor
High limit thermostat
O ring
Clip
Clip
O ring
Mynute
33
SECTION 9: EXPLODED DIAGRAMS
Table 4
2
21
27
1
2
21
9
212
4
5
12
295
200
17
18
19
13
16
221
15
Table 4 Mynute 12e - 16e - 20e
KEY DESCRIPTION
Part no 12e
Part no 16e
Part no 20e
1
2
4
4
5
9
12
13
15
16
17
18
19
21
27
200
212
295
10021252
7832
7623
7624
10021255
5172
10021254
10021253
10020897
5957
5072
3139
4007
5905
8084
5023
5080
1457
10021288
7824
10022727
7808
10021255
5172
10021254
10021253
10020897
7822
5072
3139
4007
5905
8084
5023
5080
1457
10021288
7824
10022727
7808
10021255
5172
10021254
10021253
10020897
7822
5072
3139
4007
5905
8084
5023
5080
1457
34
Air bottom box
Ambidx air box side
NG burner NP
LPG burner NP
Spark electrode
Burner plate
Gas pipe
Gas valve
Gas cock
Air box front cover
Washer
Pilot sight glass
Fixing glass flange
Washer
Air box hole cap
Washer
Self tapping screw
Silicone tube
Mynute
SECTION 9: EXPLODED DIAGRAMS
Table 5
23
22
19
25
20
295
17
14
13
16
12
296
10
300
7
2
301
4
212
3
6
Table 5 Mynute 12e - 16e - 20e
KEY DESCRIPTION
Part no 12e
Part no 16e
Part no 20e
2
3
4
6
7
10
12
13
14
16
17
19
20
22
23
25
212
295
296
300
301
5962
5271
5961
2819
5958
5963
7779
6985
7948
1140
5917
1141
8085
10023276
8086
9232
5080
1457
4807
10021269
10021270
7818
5271
7817
7813
2936
6491
7816
6985
7948
5916
5917
2939
8085
10023280
8086
9232
5080
1457
4807
10021269
10021270
7818
5271
7817
7813
2936
6491
7816
6985
7948
5916
5917
2939
8085
10023280
8086
9232
5080
1457
4807
10021269
10021270
Combustion chamber front panel
Lateral panel
Combustion chamber front panel
Combustion chamber front cover
Hood assembly
Fan
Fan to flue connector
Depressure tube
Pressure tube
Clamp for 60 diam. tube
Washer clamp
Fan flue connection
Block with combustion analysis check
Flue gas flange
Brass cap
Pressure diff. switch
Self tapping screw
Silicone tube
1/8” lock nut
Wiring harness
Wiring harness
Mynute
35
SECTION 10: LPG INSTRUCTIONS
For details of converting boilers to LPG please refer to the instructions supplied with the relevant conversion kit.
10.1 TECHNICAL DATA
12e
37 mbar
27.10 mbar
0.53 m3/h
7 x 0.77mm
Inlet pressure (LPG)
Maximum burner pressure
Gas rate
Injector size
16e
37 mbar
25.50 mbar
0.72 m3/h
9 x 0.80mm
20e
37 mbar
36.30 mbar
0.89 m3/h
9 x 0.80mm
10.2 RELATED DOCUMENTS
BS 6798
BS 5449
PART 1
BS 5546
1987
INSTALLATION OF BOILERS OF RATED INPUT NOT EXCEEDING 60 kW
1990
FORCED CIRCULATION HOT WATER SYSTEMS
1990
INSTALLATION OF GAS HOT WATER SUPPLIES FOR DOMESTIC PURPOSES
BS 5440
PART 1
1990
FLUES
BS 5482
PART 1
1994
DOMESTIC BUTANE & PROPANE GAS BURNERS IN PERMAMENT DWELLINGS
10.3
and attach a suitable manometer to the gas
valve outlet test nipple.
GAS SUPPLY
The gas supply must be connected to the
appliance by a competent LPG installer and must
be of sufficient size to supply the appliance at its
maximum output.
Light the boiler as described in 5.6 and compare the reading on the manometer with the
value described in 10.1 or fig. 25. If adjustment
is required remove the compensator tube from
the gas valve regulator.
An existing supply must be checked to ensure
that it is of adequate size to deal with the
maximum rated input of this and any other
appliances that it serves.
10.4
10.5
Locate and remove the protective screwed cap
that covers the burner pressure adjusting screw.
Adjust the screw clockwise to increase the
pressure or anti-clockwise to reduce.
GAS SUPPLY INSTALLATION
The entire installation including the meter must
be purged and checked for gas soundness.
Once the pressure has been adjusted, isolate
the appliance from the electrical supply, replace the protective screwed cap, refit the
compensator tube, remove the manometer,
and tighten the outlet test nipple.
BURNER PRESSURE
Although the burner pressure is factory set, it is
necessary to check it during commissioning,
servicing, or if the boiler has been converted.
Isolate the appliance from the electrical supply
IMPORTANT, A GAS SOUNDNESS CHECK
MUST BE CARRIED OUT.
LPG
30
Burner pressure (mbar)
25
e
12
20
e
20
e
16
15
10
5
0
7
8
9
10
11
12
13
14
Output (kW)
36
15
16
17
18
19
20
Fig. 25
Mynute
Cod. 10023279 - 12/04 - Ed. 2
Registered address:
Vokèra Ltd
Borderlake House
Unit 7 Riverside Industrial Estate
London Colney
Herts AL2 1HG
[email protected]
www.vokera.co.uk
www.vokera.ie
Sales, General Enquires
T 0844 391 0999
F 0844 391 0998
Vokèra Ireland
West Court, Callan
Co Kilkenny
T 056 7755057
F 056 7755060
Vokèra Limited reserve the right to change
specification without prior notice
Consumers statutory rights are not affected.
A Riello Group Company.
Company Reg No: 1047779